The Aesir were one of the two main tribes of deities venerated by the pre-Christian Norse and other Germanic peoples. (The second tribe was theVanir.) Most of the best-known Norse gods and goddesses belong to the Aesir, including Odin,Thor, Frigg, Tyr,Loki, Baldur,Heimdall , Idun, and Bragi. Their home is Asgard, one of the Nine Worlds, which is located in the highest, sunniest branches of the world-tree YggdrasillIn the Norse sources.Odin, the Allfather, is their chief. However, this is likely a relatively late development, and several convergent lines of evidence suggest that this role was originally occupied by Tyr.

The word Aesir is almost certainly derived from one of two Proto-Germanic words: *ansaz , pole, beam, rafter, or *ansuz , life, vitality.In either case, we see that the Aesir were thought of as being the powers that hold the cosmos together, the animating personalities of the forces of nature.